ACUS48 KWNS 221000
SWOD48
SPC AC 220958

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CST Sun Feb 22 2026

Valid 251200Z - 021200Z

...DISCUSSION...
A sharp mid-level trough will move across the US early in the
forecast period (Wednesday and Thursday -- Days 4 and 5). This wave
will induce surface cyclogenesis across the Central Plains on
Wednesday, and this low will quickly move east across the Ohio
Valley on Thursday. Southerly winds ahead of the low will draw Gulf
moisture northward across much of the Southeast.

Showers and perhaps a few thunderstorms will develop on Thursday
along and head of an eastward advancing cold front to the south of
the aforementioned surface low. Forecast soundings and low-level
wind fields show strong low-level wind fields atop a cool, moist
boundary layer. Despite little to any instability, strong
convergence along the cold front may support a narrow band of forced
ascent. Given the strength of the low-level wind fields, a few
strong wind gusts may reach the surface across portions of the
Tennessee Valley on Thursday afternoon/evening, even absent
lightning. Confidence in the specifics of this evolution are too low
to warrant severe probabilities, but will be monitored in subsequent
forecasts.

This cyclone will push a front south toward the northern Gulf coast
by Friday, where southward advancement will stall. This front should
wash out/redevelop northward next weekend as southerly flow takes
hold and begins to advect moisture northward.

..Marsh.. 02/22/2026

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ACUS48 KWNS 230838
SWOD48
SPC AC 230837

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0237 AM CST Mon Feb 23 2026

Valid 261200Z - 031200Z

...DISCUSSION...
The upper-air pattern across the US will remain characterized as
broad, fast, northwest flow for most of the forecast period.
Embedded within this flow, a series of shortwave troughs will move
across the US. The first, and potentially most impactful of these
troughs will move across the eastern US on Thursday and Friday (Days
4 and 5).

A surface low will develop across portions of the Tennessee Valley
early in the day Thursday in response to increasing large-scale
ascent associated with the aforementioned shortwave trough. This low
will quickly move east then northeast, pushing a cold front through
much of the Southeast US. A couple days of moisture return will
result in surface dewpoints in the 50Fs to perhaps low 60Fs ahead of
this cold front. Despite poor lapse rates and meager buoyancy
profiles, strong convergence along the front should yield a narrow
band of forced ascent/convection. A strong low-level jet and curved
low-level hodographs indicated in forecast soundings may support a
few isolated damaging wind gusts or perhaps a brief tornado or two
with this convection, even absent widespread lightning. Although
confidence is increasing that a band of strongly forced convection
will occur along the cold front, confidence remains too low in where
damaging wind gusts/brief tornado may occur to introduce
unconditional 15% severe probabilities.

In the wake of this cold front, the severe potential looks to be
rather limited as surface moisture is suppressed south into the
northern Gulf until next weekend at the earliest, when southerly
return flow should develop across Texas and Oklahoma.

..Marsh.. 02/23/2026

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ACUS48 KWNS 240947
SWOD48
SPC AC 240946

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0346 AM CST Tue Feb 24 2026

Valid 271200Z - 041200Z

...DISCUSSION...
The severe potential will remain low through this forecast period as
the atmosphere undergoes a pattern change.

Ensemble guidance is in good agreement that in the wake of a
departing trough, a frontal boundary will stall across the northern
Gulf Coast on Friday (Day 4), largely confining appreciable
low-level moisture to the Gulf. The front remains loosely in place
until late this weekend (Sunday -- Day 6) when it washes out and
redevelops farther north. This occurs coincident with a transition
of the upper-air pattern from a single belt of broadly northwest
flow to a split flow regime (ridge over trough).

By early next week (Days 7 and 8) an expansive upper-level ridge
will take shape across much of the US while a closed low develops
and then opens up beneath this ridge across the Southwest. The
position and evolution of the closed low should place modest
southwest flow across much of the Plains by the end of the forecast
period. Southerly winds to the east of the resulting High Plains lee
trough should support a gradual moistening of the Plains' low-level environment.

Although ensemble guidance is in relatively good agreement about the large-scale pattern evolution, considerable differences exist with
the finer details, such as quality and northward extent of the
moisture return, timing of specific feature evolution, and resulting
placement of any precipitation potential -- including thunderstorms.
In any event, the overall resulting pattern and pattern recognition
favors an increase in thunderstorm and perhaps severe potential
across the central US just beyond this forecast period.

..Marsh.. 02/24/2026

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ACUS48 KWNS 250954
SWOD48
SPC AC 250953

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0353 AM CST Wed Feb 25 2026

Valid 281200Z - 051200Z

...DISCUSSION...
Ensemble guidance continues to support a large-scale change to the
overall upper-air pattern during this forecast period. The western ridge/eastern trough should flip, evolving toward a western trough
and eastern ridge. As this happens, southwest mid-level flow into
the central US will support a gradual warming/moistening of the
Plains' low-level environment. Details of how far north and the
overall quality of the moisture return remain to be seen.

This moisture return will begin in earnest on Saturday (Day 4) as
southerly winds take hold across the central US. However, a cold
front will suppress this low-level moisture south into central Texas
on Sunday and Monday (Days 5 and 6), with some guidance members
suggesting a reinforcing frontal push on Tuesday.

By the middle of next week (Days 7 and 8), the frontal boundary
should weaken across Texas and redevelop northward. This will allow
low-level moisture to begin advancing northward into the Central
Plains. However the speed and strength of this low-level moisture
advection varies greatly between different ensembles and even within
the membership of specific ensembles. As such, the overall potential
for organized severe weather on any day looks to be too low for
unconditional probabilities. However, pattern recognition suggests
thunderstorm (and severe) potential should increase across portions
of the central US just beyond this forecast period.

..Marsh.. 02/25/2026

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ACUS48 KWNS 251040
SWOD48
SPC AC 251039

Day 4-8 Convective Outlook RESENT 1
NWS Storm Prediction Center Norman OK
0439 AM CST Wed Feb 25 2026

Valid 281200Z - 051200Z

...DISCUSSION...
Ensemble guidance continues to support a large-scale change to the
overall upper-air pattern during this forecast period. The western ridge/eastern trough should flip, evolving toward a western trough
and eastern ridge. As this happens, southwest mid-level flow into
the central US will support a gradual warming/moistening of the
Plains' low-level environment. Details of how far north and the
overall quality of the moisture return remain to be seen.

This moisture return will begin in earnest on Saturday (Day 4) as
southerly winds take hold across the central US. However, a cold
front will suppress this low-level moisture south into central Texas
on Sunday and Monday (Days 5 and 6), with some guidance members
suggesting a reinforcing frontal push on Tuesday.

By the middle of next week (Days 7 and 8), the frontal boundary
should weaken across Texas and redevelop northward. This will allow
low-level moisture to begin advancing northward into the Central
Plains. However the speed and strength of this low-level moisture
advection varies greatly between different ensembles and even within
the membership of specific ensembles. As such, the overall potential
for organized severe weather on any day looks to be too low for
unconditional probabilities. However, pattern recognition suggests
thunderstorm (and severe) potential should increase across portions
of the central US just beyond this forecast period.

..Marsh.. 02/25/2026

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ACUS48 KWNS 260958
SWOD48
SPC AC 260956

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CST Thu Feb 26 2026

Valid 011200Z - 061200Z

...DISCUSSION...
Early in the forecast period a transition across the western US will
take place as the low-amplitude ridge over the Great Basin/Southwest
shifts eastward, giving way to an amplifying trough over the West.
Several speed maxima are forecast to traverse the flow while it
remains primarily northwesterly over the central US early in the
period. At the surface, uncertainty remains regarding the southern
extent of the arctic front pushing into the Plains on Day 3.
Uncertainties in the position of this front will cause low
confidence in the projected quality of the low-level moisture
recovery across the southern Plains through Tuesday. As the
upper-air pattern across the central US transitions from
northwesterly to southwesterly, and return flow commenses, the
shallow nature of the modified arctic airmass may initially limit
the northward penetration of the richest theta-e air.

As the period progresses into Wednesday and Thursday, ensemble
guidance remains in general agreement regarding the transition to an
amplified western trough and central-to-eastern ridge. However, the
timing and phasing of individual shortwaves moving into the Plains
remains a source of forecast uncertainty.

The first meaningful shortwave is forecast to eject into the Plains
early Wednesday, inducing surface cyclogenesis that should support a
northward advancement of the warm sector. Any severe risk with this
trough on Wednesday (Day 7) will be predicated on the evolution of
the moisture return on prior days.

On Thursday, a second, more potent trough is forecast to approach
the Plains. Current ensemble guidance shows quite a bit more
variance with the timing, amplitude, and evolution of this second
trough. Some guidance brings this wave out as single, potent trough,
with other guidance suggesting a series of more subtle shortwave
troughs ejecting into the Plains from Thursday into Saturday. These discrepancies will have an impact on the location, timing, and
magnitude of any potential severe weather threat.

Despite these timing differences, the synoptic setup (increasing
low-level moisture, strengthening southwest flow aloft, repeated
cyclogenesis) is favorable for organized severe weather over the
Plains and lower Mississippi Valley. While the severe weather threat
should increase by Wednesday and Thursday (Days 7 and 8), the
specific orientation of frontal boundaries and the northward extent
of the moisture return will be highly dependent on the evolution of
the upper-lows. Given that models tend to struggle with handling the
details of pattern changes, will hold off on trying to highlight any
specific corridor for severe probabilities for Wednesday and
Thursday at this time.

..Marsh.. 02/26/2026

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ACUS48 KWNS 271001
SWOD48
SPC AC 270959

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CST Fri Feb 27 2026

Valid 021200Z - 071200Z

...DISCUSSION...
...Monday/Day 4 to Tuesday/Day 5...
At mid-levels, a trough is forecast to move across California on
Monday as zonal flow remains in place over the central and eastern
U.S. On Tuesday, the trough is forecast to move eastward across the
Desert Southwest, as flow becomes southwesterly in the south-central
states. A moist airmass will likely be in place on Monday and
Tuesday from eastern parts of the southern Plains into the lower to
mid Mississippi Valley. Thunderstorm development will be possible
each afternoon and evening across parts of the moist airmass. In
areas that destabilize the most, a marginal severe threat may
develop.

...Wednesday/Day 6 to Friday/Day 8...
On Wednesday, the trough is forecast to move into the southern and
central High Plains, as an associated mid-level jet ejects
northeastward across the southern High Plains. At the surface, a
cold front is forecast to move into the southern Plains, as a moist
airmass spreads northward from north Texas into southern and eastern
Oklahoma. As surface temperatures warm during the day, thunderstorms
appear most likely to form along the cold front, and further south
across parts of the warm sector. Moderate deep-layer shear is
evident on model forecasts which should support a severe threat
during the afternoon and evening, with a potential for large hail
and severe wind gusts. While confidence is high enough to add a
severe threat area across the southern Plains, variance does exist
concerning the timing of the shortwave trough. If the trough moves
across the southern Plains faster, then the area could need to be
adjusted.

On Thursday, the mid-level trough is forecast to eject northeastward
into the Great Lakes region, as a large upper-level trough digs into
the Desert Southwest. Southwesterly mid-level flow will likely be in
place over parts of the Great Plains, with a moist and unstable
airmass remaining over much of Texas and Oklahoma. As surface
temperatures warm, isolated strong to severe storms will be possible
in areas that destabilize the most. At this time, there is
uncertainty regarding the magnitude of the threat because some
solutions move a shortwave ridge northeastward across the
south-central U.S.

On Friday, model forecasts suggest that a large-scale upper-level
trough will move through the western U.S. Ahead of this feature,
thunderstorms will continue to be possible over parts of the
southern and central Plains, where a moist and unstable airmass is
forecast to be in place. However, a significant amount of variance
exists among the model solutions, suggesting that uncertainty is
substantial concerning the magnitude and spacing of any severe
threat.

..Broyles.. 02/27/2026

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ACUS48 KWNS 280954
SWOD48
SPC AC 280952

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0352 AM CST Sat Feb 28 2026

Valid 031200Z - 081200Z

...DISCUSSION...
...Tuesday/Day 4 and Wednesday/Day 5...
On Tuesday, a mid-level trough will move eastward across the Desert
Southwest, as southwesterly flow remains in place over the southern
Plains. As the trough approaches Tuesday night, scattered elevated thunderstorms will be possible from the Red River northeastward into
the mid Mississippi Valley. From Tuesday night into Wednesday, a
moist airmass will spread northward from east-central Texas into the
Arklatex and Ozarks. Thunderstorm development will be possible near
the boundary from central Oklahoma into southern Missouri during the
day on Wednesday, and further southeast across the warm sector in
the afternoon and evening. Model forecasts continue to show moderate instability ahead of the front. In addition, a mid-level jet streak
is forecast to pass through the southern Plains during the
afternoon, creating deep-layer shear sufficient for severe storms.
Supercells with wind damage and isolated large hail will be
possible. Model solutions are in better agreement this run,
suggesting the severe threat will be a bit further east than was
previously forecast. For this reason, the severe threat area has
been adjusted eastward towards the Ark-La-Tex.

...Thursday/Day 6 to Saturday/Day 8...
On Thursday, the shortwave trough is forecast to move through the
mid Mississippi Valley, as the cold front advances southeastward
into the Ark-La-Tex and mid Mississippi Valley. Thunderstorms will
be possible near the front during the day into the evening.
Deep-layer shear and instability are forecast to be somewhat
limited, which should keep any severe threat marginal.

From Thursday night into Friday, southwesterly mid-level flow is
forecast to strengthen over the south-central states. In response,
moisture advection will likely continue over the southern Plains as
moderate instability re-develops across much of the southern Plains.
Scattered thunderstorms should form over parts of this airmass
Thursday night from west-central Texas north-northeastward into
parts of the central Plains. The potential for storm development
should continue into Friday along the northern edge of the moist
airmass from north-central Texas northeastward into the Ozarks.
Although a severe threat could develop over parts of the southern
Plains and Ozarks Friday afternoon and evening, there is
considerable uncertainty, mainly due to variance among model
solutions.

On Saturday, am amplified upper-level trough is forecast to develop
over the western U.S., as mid-level flow becomes south-southwesterly
from the Gulf Coast States into the mid Mississippi Valley. A moist
airmass is forecast over much of the Gulf Coast states, where
scattered thunderstorms will be possible during the day. Although a
severe threat could develop during the day, uncertainty is high
concerning the placement of a more concentrated severe threat area.

..Broyles.. 02/28/2026

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ACUS48 KWNS 011001
SWOD48
SPC AC 010959

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CST Sun Mar 01 2026

Valid 041200Z - 091200Z

...DISCUSSION...
...Wednesday/Day 4 to Thursday/Day 5...
On Wednesday, model forecasts continue to move a mid-level shortwave
trough across the southern Plains. A cold front is forecast to
advance southeastward into Oklahoma as a moist and unstable airmass
resides southward from the front over much of the southern Plains.
Surface dewpoints across southeast Oklahoma and north-central to
northeast Texas should be in the lower to mid 60s F, and moderate
instability will be possible by afternoon. Thunderstorm development
appears likely across parts of this unstable airmass from the mid
afternoon into the evening. Moderate deep-layer shear should support
a severe threat, with a potential for large hail and damaging wind
gusts associated with supercells.

On Thursday, the shortwave trough is forecast to move into the mid
Mississippi Valley, as a much larger upper-level trough moves
through the Desert Southwest. A moist and unstable airmass should
remain in place over the southern Plains. However, large-scale
ascent should be weak between these two systems, which should dampen
the severe potential across most of the south-central U.S. The most
likely location for an isolated to marginal severe threat would be
in the Ark-La-Tex Thursday afternoon.

...Friday/Day 6 to Sunday/Day 8...
At mid-levels, southwest flow is forecast across much of the central
U.S. on Friday, as a large trough remains over the southwestern
states. Moisture advection is expected to continue over the Great
Plains and Upper Midwest along a corridor of strong low-level flow.
Model forecasts are in general agreement that moderate instability
will develop over much of this airmass by Friday afternoon, and that
scattered thunderstorms will form. Convective development will be
supported by the right entrance region of a mid-level jet ejecting northeastward through the central Plains. This mid-level jet will be
associated with moderate to strong deep-layer shear, supporting
scattered severe storms potentially across a large part of the moist
sector. The current thinking is that the severe threat will be
maximized during the late afternoon and evening from central Texas northeastward into the lower Missouri Valley. Large hail and
damaging wind gusts are expected to the primary threats, but a few
tornadoes remain possible.

On Saturday, the upper-level system in the central U.S. is forecast
to move into the Great Lakes region, as a cold front advances
quickly southeastward into the western Gulf Coast states, and lower
Mississippi Valley. An isolated severe threat could develop ahead of
the front Saturday afternoon, but confidence is low concerning the
spatial distribution of any threat. On Sunday, isolated to scattered thunderstorms will again be possible in the Gulf Coast region.
However, deep-layer shear is forecast to be weak over much of this
area, suggesting any severe potential should remain marginal.

..Broyles.. 03/01/2026

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ACUS48 KWNS 020959
SWOD48
SPC AC 020958

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CST Mon Mar 02 2026

Valid 051200Z - 101200Z

...DISCUSSION...
...Thursday/Day 4 and Friday/Day 5...
At mid-levels, a shortwave trough is forecast to move through the
mid Mississippi Valley on Thursday as flow remains southwesterly
across the south-central U.S. An upper-level system will be located
in the Desert Southwest. At the surface, moisture advection is
forecast across the southern Plains, where surface dewpoints will be
mostly in the 50s and 60s F by afternoon. As surface temperatures
warm during the day, an axis of moderate instability is forecast to
develop to the east of a dryline from west-central Texas
north-northeastward into the eastern Texas Panhandle and western
Oklahoma. Along this axis of instability, moderate deep-layer is
forecast, along with steep mid-level lapse rates. This will likely
support a severe threat during the afternoon and evening. Supercells
with large hail, damaging wind gusts and a tornado threat will be
possible.

On Friday, mid-level southwesterly flow will strengthen across parts
of the southern and central Plains, as a mid-level jet ejects
northeastward into the central U.S. At the surface, a moist airmass
with moderate instability is forecast to be in place by afternoon
from north-central Texas north-northeastward into the lower Missouri
Valley. Model forecasts are in agreement that scattered
thunderstorms will develop across this unstable airmass during the
afternoon and evening. Moderate deep-layer shear and steep mid-level
lapse rates should be favorable for supercells with large hail. Wind
damage and tornadoes will also be possible with supercells and
bowing line segments. Some solutions suggest that the threat will
persist into the overnight period as a low-level jet ramps up across
the region.

...Saturday/Day 6 to Monday/Day 8...
Mid-level southwesterly flow is expected to continue over the
south-central U.S. on Saturday, as a cold front moves southward
across the southern Plains and Ozarks. To the south of the front,
the models forecast pockets of moderate instability, and suggest
that scattered to numerous thunderstorms will develop. In addition,
moderate to strong deep-layer shear is forecast across the northern
edge of the moist sector. Model consensus suggests that a severe
threat will develop Saturday afternoon and evening, mainly from
west-central Texas northeastward into the western Ozarks.

The cold front is forecast to continue moving southward into the
western Gulf Coast states on Sunday. Scattered thunderstorms are
forecast to develop near and to the south of the front Sunday
afternoon, where an isolated severe threat will be possible.
Confidence is low concerning the spatial distribution of any
potential threat. On Monday, a shortwave ridge is forecast to move
over the top of a moist airmass in the southern Plains. This
scenario could support an isolated severe threat in the afternoon.
However, uncertainty is high at this range in the forecast period.

..Broyles.. 03/02/2026

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ACUS48 KWNS 030954
SWOD48
SPC AC 030952

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0352 AM CST Tue Mar 03 2026

Valid 061200Z - 111200Z

...DISCUSSION...
...Friday/Day 4 and Saturday/Day 5...
A strong upper-level system is forecast to eject northeastward into
the central High Plains on Friday, as an associated 60 to 80 knot
mid-level jet translates northeastward ahead of the trough. At the
surface, a moist and unstable airmass will likely be in place from
central and east Texas northward into the lower Missouri Valley.
Warming surface temperatures and increasing low-level convergence
will support scattered convective initiation to the west of the
moist axis. Storms are expected to grow upscale in the mid to late
afternoon, moving eastward toward an axis of strong low-level flow.
Moderate instability, strong deep-layer shear and steep lapse rates
will be favorable for supercells. Supercells should be capable of
producing tornadoes, large hail and severe wind gusts. The greatest
potential is forecast from near the Red River in north Texas north-northeastward across eastern Oklahoma into eastern Kansas and northwestern Missouri, where a 30 percent contour has been added. A
severe threat is also forecast northeastward into parts of the mid
to upper Mississippi Valley, where strong deep-layer shear and
sufficient low-level moisture will be in place for a severe threat.

On Saturday, the upper-level system is forecast to move through the north-central U.S., as a cold front advances southeastward into the
Ark-La-Tex, mid Mississippi Valley, and lower Great Lakes. Scattered
to numerous thunderstorms are expected to develop ahead of the front
during the day as surface temperatures warm. It appears that a
marginal severe threat will develop during the mid to late afternoon
over much of the northwestern edge of the moist sector from the
Ark-La-Tex northeastward into the Ohio Valley.

...Sunday/Day 6 to Tuesday/Day 8...
On Sunday in the mid-levels, a 90 to 110 knot jet is forecast to
move into the northern U.S., as westerly flow remains over much of
the east-central U.S. A front is forecast to become quasi-stationary
from the Ozarks eastward into the southern Appalachians. Isolated to
scattered thunderstorms with a marginal severe threat may develop to
the south of the front during the afternoon.

On Monday and Tuesday, moisture advection is forecast to take place
from the central Plains into the Great Lakes, as mid-level flow
again becomes southwesterly. Moisture and instability should be
favorable for isolated severe storms Monday afternoon in areas that
heat up sufficiently. On Tuesday, models forecast a strong
upper-level system to eject northeastward into the south-central
U.S. If this scenario works out, a greater severe threat appears
possible Tuesday afternoon and evening over the southern and central
Plains. However, uncertainty is considerable at this range in the
forecast period due to a relatively wide spread in the model
guidance.

..Broyles.. 03/03/2026

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ACUS48 KWNS 040958
SWOD48
SPC AC 040956

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CST Wed Mar 04 2026

Valid 071200Z - 121200Z

...DISCUSSION...
...Saturday/Day 4 and Sunday/Day 5...
On Saturday at mid-levels, a shortwave trough is forecast to move
eastward across the north-central U.S., as flow remains
southwesterly from the southern Plains to the Eastern Seaboard. A
cold front is forecast to move southeastward across the southern
Plains, Ozarks, mid Mississippi Valley and Ohio Valley. Surface
dewpoints ahead of the front are forecast to be mostly in the 60s F
with pockets of moderate instability developing in the afternoon.
Scattered to numerous thunderstorms are expected to develop and move southeastward into the moist airmass. Although an isolated severe
threat will be likely in some areas, uncertainty is considerable
concerning the area with the greatest severe threat. The current
thinking is that the severe threat will be concentrated in two
areas, with one being from south-central Texas northeastward into
northern Louisiana, and a second being located in the Ohio Valley. A
15 percent area may need to be added in either of these two areas in
later outlooks.

On Sunday, a moist and unstable airmass is forecast along the
western Gulf Coast. Isolated storms associated with a marginal
severe threat could develop in the afternoon. Large-scale ascent
will be limited which should keep any severe potential localized.

...Monday/Day 6 to Wednesday/Day 8...
West-southwesterly mid-level flow is forecast to continue on Monday
across much of the central and eastern U.S. Low-level moisture
return is forecast to take place over the southern and central
Plains, where the models suggest moderate instability will be
possible by afternoon. As a low-level jet strengthens during the
afternoon and evening, isolated to scattered thunderstorms should
develop in areas that heat up sufficiently. A severe threat would be
possible. However, spatial uncertainty exists concerning where any
severe threat will be the greatest.

On Tuesday, model forecasts are in general agreement, moving an
upper-level trough northeastward into the southern High Plains. An
associated mid-level jet is forecast to eject northeastward ahead of
the system. Model forecasts suggest that the airmass ahead of the
trough will become moderately unstable by Tuesday afternoon. This
combined with strong large-scale ascent should support scattered
severe storms in the afternoon and evening. The favored severe
threat area is expected from parts of the southern and central
Plains eastward into the Ozarks.

On Wednesday, the upper-level trough is forecast to move across the south-central U.S., as a cold front advances eastward into the
Southeast. A severe threat may again develop Wednesday afternoon as
the airmass ahead of the front becomes unstable. However, there is
considerable model spread concerning the timing of features at this
extended range.

..Broyles.. 03/04/2026

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ACUS48 KWNS 050938
SWOD48
SPC AC 050936

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0336 AM CST Thu Mar 05 2026

Valid 081200Z - 131200Z

...DISCUSSION...
...Sunday/Day 4 and Monday/Day 5...
A moist airmass in the Gulf Coast region on Sunday will advect
northward into the east-central U.S. on Monday. Over the top of this
airmass, west-southwesterly mid-level flow will be in place.
Although large-scale ascent is forecast to be limited on both days,
isolated strong to marginally severe thunderstorms will be possible
in the afternoon in areas that heat up sufficiently. The greatest
potential for severe storms appears to be on Monday afternoon in the Ark-La-Tex, where moisture and low-level flow are currently forecast
to be maximized.

...Tuesday/Day 6 to Thursday/Day 8...
On Tuesday, model forecasts move an upper-level system across
northern Mexico, and retain southwesterly mid-level flow over much
of the south-central U.S. A moist and unstable airmass is forecast
over much of the southern and central Plains eastward into the lower
to mid Mississippi Valley. It appears that large-scale ascent
associated with the upper-level trough will gradually increase over
the southern and central Plains on Tuesday. In response, scattered thunderstorms should develop over parts of the moist sector Tuesday
afternoon and evening. Although model forecasts have slowed the
progression of the upper-level low, a belt of strong mid-level flow
is still forecast over the south-central U.S. on Tuesday. This
suggests that deep-layer shear will support severe thunderstorm
development, potentially across a broad area. The severe threat is
expected to continue from evening into the overnight period as the
upper-level trough approaches.

On Wednesday, the upper-level trough and an associated cold front is
forecast to move into the western Gulf Coast states. Ahead of the
system, a moist and unstable airmass appears likely by afternoon.
Thunderstorms that develop near and ahead of the front could have a
severe threat. However, there are still questions about the timing
of the trough and front. If model runs continue to suggest that the
system will move into the western Gulf Coast states on Wednesday,
then a risk area may need to be added. An isolated risk may also
develop on Wednesday northeastward ahead of the front in parts of
the Tennessee and Ohio Valleys.

On Thursday, the upper-level trough is forecast to move into the
eastern U.S., as the cold front moves offshore into the western
Atlantic. Thunderstorms with an isolated severe threat would be
possible along parts of the Eastern Seaboard before the front
passes. However, uncertainty at this extended range is considerable.

..Broyles.. 03/05/2026

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ACUS48 KWNS 060940
SWOD48
SPC AC 060938

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0338 AM CST Fri Mar 06 2026

Valid 091200Z - 141200Z

...DISCUSSION...
...Day 4/Monday...

A weak upper shortwave impulse is expected to migrate across the
Ozarks/Lower MS Valley on Monday. This will support a narrow
corridor of enhanced westerly flow aloft atop a moistening boundary
layer. Isolated thunderstorms may develop across the ArkLaTex to
Lower MS Valley vicinity within the warm advection regime, and few
storms could become strong to locally severe. However, modest
forcing and otherwise lack of low-level focus precludes a 15 percent delineation.

...Day 5/Tuesday into Day 6/Wednesday...

An upper low and attendant shortwave trough over northwest Mexico is
forecast to eject eastward toward the southern High Plains on
Tuesday. At the same time, a broad upper trough within northern
stream flow will develop east from the northern Plains to the Upper
Midwest. As this occurs, a belt of enhanced southwesterly flow aloft
will overspread a large warm/moist sector from the southern Plains
to the Mid/Lower MS and Ohio Valleys. A complex surface pattern is
expected to emerge, influenced by the split-flow upper troughing
pattern. A baroclinic zone extending from OK the Mid-MS Valley area
will be one focus for severe thunderstorm potential. Meanwhile, lee
surface troughing across west TX and a developing dryline will be
another focus for severe storm development. While details remain
uncertain, these surface features, combined with strengthening
southwesterly flow overspreading a warm and unstable airmass, will
likely foster a broad area of severe thunderstorm potential from the
southern Plains into the Midwest.

As the upper troughs from Day 5/Tuesday continue east across the
southern Plains and Great Lakes on Day 6/Wednesday, a cold front is
expected to develop southeast across the Ohio Valley into east
Texas. Spread among forecast guidance increases during this time,
leading to more uncertainty. However, most guidance has some overlap
of favorable low-level moisture and instability with stronger
mid/upper level flow across portions of east TX into the Lower MS
valley. As a result, a 15 percent area has been delineated. This
area my need to shift/expand northeast with time depending on trends
in model guidance, but currently, it is uncertain if sufficient
destabilization will occur further northeast, precluding severe
probabilities into the TN/OH Valleys vicinity.

...Days 7-8/Thursday-Friday...

Predictability is low toward the end of the forecast period as
forecast model spread continues to increase. While it is plausible
some severe risk could persist into the Southeast on Day 7/Thursday
as the upper trough over the Lower MS Valley continues to migrate
east, uncertainty is too high to include probabilities at this time.

..Leitman.. 03/06/2026

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ACUS48 KWNS 061047
SWOD48
SPC AC 061046

Day 4-8 Convective Outlook CORR 1
NWS Storm Prediction Center Norman OK
0446 AM CST Fri Mar 06 2026

Valid 091200Z - 141200Z

CORRECTED FOR TEXT

...DISCUSSION...
...Day 4/Monday...

A weak upper shortwave impulse is expected to migrate across the
Ozarks/Lower MS Valley on Monday. This will support a narrow
corridor of enhanced westerly flow aloft atop a moistening boundary
layer. Isolated thunderstorms may develop across the ArkLaTex to
Lower MS Valley vicinity within the warm advection regime, and a few
storms could become strong to locally severe. However, modest
forcing and otherwise lack of low-level focus precludes a 15 percent delineation.

...Day 5/Tuesday into Day 6/Wednesday...

An upper low and attendant shortwave trough over northwest Mexico is
forecast to eject eastward toward the southern High Plains on
Tuesday. At the same time, a broad upper trough within northern
stream flow will develop east from the northern Plains to the Upper
Midwest. As this occurs, a belt of enhanced southwesterly flow aloft
will overspread a large warm/moist sector from the southern Plains
to the Mid/Lower MS and Ohio Valleys. A complex surface pattern is
expected to emerge, influenced by the split-flow upper troughing
pattern. A baroclinic zone extending from OK to the Mid-MS Valley
area will be one focus for severe thunderstorm potential. Meanwhile,
lee surface troughing across west TX and a developing dryline will
be another focus for severe storm development. While details remain
uncertain, these surface features, combined with strengthening
southwesterly flow overspreading a warm and unstable airmass, will
likely foster a broad area of severe thunderstorm potential from the
southern Plains into the Midwest.

As the upper troughs from Day 5/Tuesday continue east across the
southern Plains and Great Lakes on Day 6/Wednesday, a cold front is
expected to develop southeast across the Ohio Valley into east
Texas. Spread among forecast guidance increases during this time,
leading to more uncertainty. However, most guidance has some overlap
of favorable low-level moisture and instability with stronger
mid/upper level flow across portions of east TX into the Lower MS
Valley. As a result, a 15 percent area has been delineated. This
area may need to shift/expand northeast with time depending on
trends in model guidance, but currently, it is uncertain if
sufficient destabilization will occur further northeast, precluding
severe probabilities into the TN/OH Valleys vicinity.

...Days 7-8/Thursday-Friday...

Predictability is low toward the end of the forecast period as
forecast model spread continues to increase. While it is plausible
some severe risk could persist into the Southeast on Day 7/Thursday
as the upper trough over the Lower MS Valley continues to migrate
east, uncertainty is too high to include probabilities at this time.

..Leitman.. 03/06/2026

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ACUS48 KWNS 070836
SWOD48
SPC AC 070834

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0234 AM CST Sat Mar 07 2026

Valid 101200Z - 151200Z

...DISCUSSION...
...Days 4-5/Tue-Wed...

An active pattern with severe thunderstorm potential is expected
Tuesday and Wednesday from the southern Plains to the Mid/Lower MS
and OH Valleys. Medium range guidance is in fairly good agreement
during this time. Starting on Tuesday, an upper low over northern
Mexico will shift east/northeast, becoming an open wave as it begins
to merge with a northern stream upper trough developing southeast
across the northern/central Plains through early Wednesday. A belt
of strong southwesterly deep-layer flow will overspread a large warm
sector on Tuesday. Lee cyclogenesis is forecast across the
central/southern High Plains, along with a second surface low
developing over IA as the northern stream upper trough approaches.
This setup will allow for a sharpening dryline/Pacific front across
the southern Plains, while a cold front develops southeast into the
MO/Mid-MS Valley overnight. Strong ascent should focus thunderstorm
development across the warm sector ahead of these surface boundaries
within a strongly sheared environment, and potentially widespread
severe thunderstorm activity is possible.

The large-scale upper trough and attendant surface cold front will
continue to progress eastward on Wednesday. Uncertainty does
increase, especially with north and east extent of severe potential.
How far east convection develops on Tuesday and how much downstream destabilization occurs is somewhat unclear. Nevertheless, a
deepening surface cyclone is forecast to develop northeast from the
Great Lakes into Ontario and Quebec, while strong deep layer
southwesterly flow overspreads a moist warm sector ahead of the
surface front. This should set the stage for at least isolated to
scattered severe thunderstorm potential along the length of the cold
front through Wednesday evening.

Given uncertainties mentioned above, these areas are likely to be
adjusted in coming days as details become better resolved, but the
overall pattern should support a couple of active severe weather
days over a broad area.

...Day 6/Thu...

Uncertainty increases by Thursday as spread among medium range
guidance increases quite a bit with respect to the evolution/timing
of the upper trough. Some severe potential could persist/develop
across the Mid-Atlantic region, but predictability is too low to
include a 15 percent delineation at this time.

Beyond Thursday, severe thunderstorm potential will likely be low as
the upper pattern become lower amplitude and stronger westerly flow
remains confined to the northern tier of the U.S., along with Gulf
moisture largely remaining offshore behind the cold frontal passage.

..Leitman.. 03/07/2026

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ACUS48 KWNS 080916
SWOD48
SPC AC 080914

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0414 AM CDT Sun Mar 08 2026

Valid 111200Z - 161200Z

...DISCUSSION...
...Day 4/Wed...

A large-scale upper trough will continue to shift east across the
central U.S. on Wednesday, becoming oriented from the Upper Great
Lakes to the central Gulf coast vicinity by Thursday morning. An
embedded shortwave within the base of this trough will move from the
southern Plains to the Deep South, while the northern branch of the
trough moves across the Midwest. Strong deep-layer southwesterly
flow will overspread a broad warm sector across much of the Midwest
and southern U.S. Meanwhile, a cold front will develop southeast
through the period, tracking across much of the Mid/Lower MS, OH and
TN Valleys.

Uncertainty exists regarding where convection may be ongoing
Wednesday morning, and some potential exists for widespread
thunderstorm activity across parts of the Midwest. As a result, it
is uncertain how far north quality thermodynamics will exist.
Nevertheless, it appears likely at least some severe risk will exist
across the Ohio Valley given favorable boundary-layer moisture and
impressive vertical shear profiles. Further southwest toward the
Lower MS Valley into the Deep South vicinity, morning convection may
be more limited compared to further north, allowing for more
extensive destabilization ahead of the surging cold front. A
mixed-mode of supercells ahead of the cold front, and an organized
line of storms along the cold front will be possible across this
area.

As mesoscale details become better resolved in the coming days, the
severe area for Wednesday is likely to shift some. However, the
overall pattern suggests a broad area of severe thunderstorm
potential is probable on Wednesday.

...Day 5/Thu...

Some severe thunderstorm potential could persist into portions of
the Mid-Atlantic and Southeast. However, uncertainty is fairly high
given this potential will depend on evolution of convection on Day
4/Wed, which could be quite extensive and outpace the surface front
Wednesday night into early Day 5/Thu. As such, predictability is
low.

...Days 6-8/Fri-Sun...

Severe thunderstorm potential appears low during the weekend as
broad upper troughing persists across the central/eastern U.S.

..Leitman.. 03/08/2026

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ACUS48 KWNS 090833
SWOD48
SPC AC 090831

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0331 AM CDT Mon Mar 09 2026

Valid 121200Z - 171200Z

...DISCUSSION...
...Day 4/Thu...

Some low-end severe thunderstorm risk could persist into Day 4/Thu
across portions of the Southeast as an upper trough pivots toward
the Atlantic coast in tandem with an eastward-advancing surface cold
front. Ahead of the front, a moist airmass will be in place from
GA/FL northeast toward southeast VA. Convection will likely be
ongoing Thursday morning, and persistent warm advection will result
in widespread cloudiness. This will limit destabilization and lapse
rates are expected to remain modest. Overall, severe potential
appears less than 15 percent.

...Days 5-8/Fri-Mon...

Severe thunderstorm potential appears low Friday and Saturday as a
prior cold frontal passage into the Gulf leaves a dearth of boundary
layer moisture in its wake. Another upper trough is expected to
deepen over the Plains and the eastern U.S. late in the period. Some
moisture return may occur ahead of this feature before another cold
front develops southeast across the eastern half of the CONUS. This
could bring some increasing thunderstorm potential to parts of the south-central or southeast U.S., however, at this time any better
moisture return looks displaced to the south of stronger flow aloft.

..Leitman.. 03/09/2026

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